| 摘要 |
<p>#CMT# #/CMT# The gearbox has a spacing unit mounted on a central support (19), and pivoting from a clutched position to a released position when speed selecting units are actuated. Rollers cooperate with ramps on bushings integrated with motor and receiver plates, to separate the support and the motor plate relative to the receiver plate and the support, respectively, during pivoting of the unit to the released position. The support has a control cam follower (20) connected in rotation to another follower (21) by a gimbal joint (27). A ring is placed between each pinion (28) and relating cam follower. #CMT#USE : #/CMT# Used in a cycle (claimed) for driving in rotation a rear wheel of the cycle. #CMT#ADVANTAGE : #/CMT# The cam follower of the central support is connected in rotation to another cam follower by the gimbal joint, thus providing mechanical precision of the gearbox, and eliminating the need of adjusting the position of parts of the gearbox with respect to each other, and hence rapidly assembling the gearbox with reduced cost and providing greater flexibility of the gearbox. The structure of the gearbox permits to automatically separate the plates during gear shifting without the need of a cyclist to stop pedaling of the cycle. The structure of the gearbox permits a simple control rod to actuate the spacing unit, thus eliminating the need of utilizing pistons and a hydraulic circuit, and hence permitting to maintain one of the two plates to be fixed in translation with respect to a case. The arrangement of the central support permits a better distribution of force on pinions. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows a perspective view of a central part provided with pinions and cam followers. 19 : Central support 20, 21 : Cam followers 22 : Rod 27 : Gimbal joint 28 : Pinions #CMT#POLYMERS : #/CMT# The ring is made of polyurethane.</p> |
